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991.
PurposeTo evaluate the impact of a versatile flexible ceiling-mounted C-arm on active table and gantry repositioning during interventions and its effect on operator discomfort, system usability, and patient safety compared with a traditional ceiling-mounted system.Materials and MethodsThere were 100 IR procedures studied: 50 in a traditional IR system (standard group) and 50 with a novel multiaxis ceiling-mounted system (test group). FlexArm was capable of multiple gantry rotation points allowing increased access to the patient in addition to 236 cm of lateral x-ray detector travel. For each procedure, both the table and the gantry repositioning were measured. Patient safety, patient/equipment repositioning effort, and physical discomfort were evaluated through an operator survey.ResultsTable repositioning was reduced from 42 to 16 instances per procedure (P < .001) in the test group compared with the standard group. The operators perceived less table and gantry repositioning effort (P < .0001) and decreased risks of equipment collisions, displacement of vascular access, and dislodgment of tubes/lines with the test group (P < .0001). Operator discomfort was reduced for all body areas in the test group over the standard group (P < .0001).ConclusionsThe FlexArm system geometry enhances operator ergonomics, as there was a decrease need to move the table, leading to a perceived decrease in patient risk and decrease operator physical discomfort when compared to a traditional imaging system.  相似文献   
992.

Purpose

The purpose of this study was to compare patient-reported outcomes (PROs), morbidity, and costs of TLIF vs PLF to determine whether one treatment was superior in the setting of single-level degenerative spondylolisthesis.

Methods

Patients undergoing TLIF or PLF for single-level spondylolisthesis were included for retrospective analysis. EQ-5D, ODI, SF-12 MCS/PCS, NRS-BP/LP scores were collected at baseline and 24 months after surgery. 90-day post-operative complications, revision surgery rates, and satisfaction scores were also collected. Two-year resource use was multiplied by unit costs based on Medicare payment amounts (direct cost). Patient and caregiver workday losses were multiplied by the self-reported gross-of-tax wage rate (indirect cost). Total cost was used to assess mean total 2-year cost per QALYs gained after surgery.

Results

62 and 37 patients underwent TLIF and PLF, respectively. Patients in the PLF group were older (p < 0.01). No significant differences were seen in baseline or 24-month PROs between the two groups. There was a significant improvement in all PROs from baseline to 24 months after surgery (p < 0.001). Both groups had similar rates of 90-day complications, revision surgery, satisfaction, and similar gain in QALYs and cost per QALYs gained. There was no significant difference in 24-month direct, indirect, and total cost.

Conclusions

Overall costs and health care utilization were similar in both the groups. Both TLIF and PLF for single-level degenerative spondylolisthesis provide improvement in disability, pain, quality of life, and general health.
  相似文献   
993.
Purpose

This study aimed to investigate the relationship between knee extensors maximum voluntary contraction (MVC) torque and rate of torque development (RTD) with jump performance and with echography intensity (EI) from the vastus lateralis muscle (VL).

Methods

We assessed the MVC torque and RTD from knee extensors by a standard isokinetic device from 16 male professional soccer players (25.5?±?3.9 years). Counter-movement jump (CMJ) and squat jump (SJ) height were calculated from their flight times. EI was determined from VL ultrasound images’ grayscale histogram acquired in the middle of the tight. Correlation between variables was investigated by the Pearson correlation coefficient.

Results

We observed a VL EI of 26.4?±?7.8 a.u., and the SJ and CMJ heights were 36.0?±?3.0 and 36.2?±?4.1 cm, respectively. There was a significant correlation between the MVC torque and absolute late-phase RTD (r?=?0.67 and 0.76—RTD200 and RTD250, respectively), between the CMJ height and absolute RTD50 (r?=?0.50), and between the normalized early-phase RTD and SJ height (r?=?0.53–0.60—RTD50 and RTD150). Additionally, normalized RTD200 (r?=?? 0.51) and RTD250 (r?=?? 0.56) were negatively correlated with EI.

Conclusions

Such results suggest that athletes with the ability to produce torque explosively in the very beginning (between 50 and 150 ms) of knee extension can jump higher. Also, the muscle quality assessed by the VL IE seems to be more important to maximum strength and later periods of torque rise (>?200 ms).

  相似文献   
994.
995.
Cell transplantation to improve ventricular function in the failing heart   总被引:9,自引:0,他引:9  
Current therapies for congestive heart failure are limited in efficacy or in applicability. Cardiac cell transplantation offers a novel therapeutic approach to improve heart function. Although significant progress has been made over the past decade in the development of cell transplantation, only recently have investigators studied the changes in ventricular function following cell transplantation. This review article describes the latest research developments, evaluates recent studies of ventricular function after cell transplantation, and discusses the future directions of cell transplantation as a new therapy to ‘repair broken hearts’.  相似文献   
996.
John S. Rhee  MD  MPH    B. Alex Matthews  Ph  D  Marcy Neuburg  MD    Timothy L. Smith  MD  MPH    Mary Burzynski  RN    Ann B. Nattinger  MD  MPH 《Dermatologic surgery》2004,30(4):525-529
Background. Quality of life (QOL) has been identified as an important outcome in cancer research, yet the most common malignancy among humans, nonmelanoma skin cancer (NMSC), has been poorly studied in this regard.
Objective. To determine whether change occurred in the QOL of NMSC patients after surgery using a general, validated dermatology QOL instrument: the Dermatology Life Quality Index (DLQI).
Methods. A prospective study was conducted on 121 consecutive patients referred to a dermatologic Mohs surgery clinic with NMSC of the head and neck. QOL assessment was performed using the DLQI before (n=121) and after surgical treatment at 4 months (n=101).
Results. QOL scores demonstrated little handicap at initial diagnosis. The total DLQI scores showed little change over time, but an item analysis revealed that 2 of the 10 items demonstrated statistically significant change over time, with QOL improving after treatment—decreased painfulness/itchiness/soreness and less necessity to use concealing clothing.
Conclusions. General dermatology QOL instruments demonstrated minimal handicap at initial diagnosis and little change after treatment of NMSC. Although the associations were modest, improvement in some aspects of well-being after treatment of NMSC was demonstrated. A more disease-specific instrument may be necessary to study this disease process further.  相似文献   
997.
Poly (ADP-ribose) polymerase (PARP) is a nuclear enzyme that consumes NAD in response to DNA strand breaks. The PARP inhibitor nicotinamide prevents NAD consumption and protects islet beta-cells from chemically induced necrosis but not cytokine-induced apoptosis. Therefore, it is unclear how nicotinamide protects NOD mice from autoimmune diabetes in which apoptosis is the mode of beta-cell death. To investigate the mechanism of diabetes prevention by PARP inhibition, we studied the effects of a novel, potent PARP inhibitor, PJ34, a phenanthridinone derivative, on diabetes development in NOD mice and on diabetes recurrence in diabetic NOD mice transplanted with syngeneic islets. PJ34 administration from age 5 or 15 weeks significantly decreased insulitis, beta-cell destruction and diabetes incidence, and protection from diabetes continued for 12 weeks after PJ34 therapy was stopped. Similarly, syngeneic islet graft survival was prolonged and outlasted therapy in PJ34-treated mice. Immunohistochemical studies revealed significantly fewer leukocytes in islet grafts of PJ34-treated mice, together with increased apoptosis of these cells and decreased expression of the T helper 1-type cytokine interferon (IFN)-gamma. These results suggest that PARP inhibition protects against autoimmune beta-cell destruction in NOD mice by inducing apoptosis of islet-infiltrating leukocytes and decreasing IFN-gamma expression in the islets.  相似文献   
998.
We investigated the effect of sequential administration of intrathecal (IT) hyperbaric bupivacaine (after the initial administration of IT hypobaric fentanyl) on the duration of spinal analgesia. Thirty-seven nulliparous parturients with a cervical dilation >/= 5 cm were randomized to receive either IT fentanyl 25 micro g and plain bupivacaine 2.5 mg (group P; n = 19) or IT fentanyl 25 micro g and hyperbaric (with 8% glucose) bupivacaine 2.5 mg (group H; n = 18). The two components of the IT injectate were administered sequentially (fentanyl 25 micro g diluted in 2 mL of normal saline, immediately followed by 0.5 mL of 0.5% bupivacaine). Patients were then positioned with their torso elevated at 30 degrees for 30 min. Pain scores using 0-100 visual analog scales were collected before combined spinal/epidural analgesia and at 5, 15, and 30 min after the block. Patients in Group H had a longer median duration of analgesia (122 min; range, 80-210 min) than Group P (95 min; range, 75-125 min) (P < 0.01). Group H also had a more limited dermatomal spread (median highest sensory level of T8 versus T4 in group P; P < 0.05). The side-effect profile was similar. Under these circumstances, hyperbaric bupivacaine conferred an increased duration of IT analgesia compared with plain bupivacaine.  相似文献   
999.
Seventy-six patients with acute inferior acute myocardial infarction (AMI) and advanced atrioventricular (AV) block are described. According to pre-established ECG criteria and time of appearance of the advanced AV block, patients were divided into two groups. The early block group consisted of 31 patients who developed advanced AV block during the hyperacute ECG stage of AMI. Advanced AV block in these patients was characterized by early appearance, short duration, third-degree type block, poor response to atropine, and increased need for pacemaker therapy. The late block group consisted of 45 patients who developed advanced AV block during subsequent ECG stages of AMI. Advanced AV block in these patients was characterized by late appearance, longer duration, second-degree type block, positive response to atropine, and diminished need for pacemaker therapy. Morbidity and mortality also differed between both groups. Patients with early block had more syncope (32% vs 2%, p < 0.0001), more left heart failure (36 vs 7%, p < 0.005), and more cardiogenic shock (39% vs 2%, p < 0.001) than patients with late block. The mortality rate in the early block group was high (23%) and similar to that reported in the literature, whereas the mortality rate in the late block group was low (7%, p < 0.05) and similar to the mortality rate reported for acute inferior AMI without advanced AV block. These data identify a subgroup of patients with acute inferior AMI and advanced AV block, which accounts for the high mortality rate reported in this group of patients.  相似文献   
1000.
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